Methods for using dental compositions containing fluorescent agents

ABSTRACT

A method of applying a dental composition to tooth surfaces is provided. The dental composition, comprising polymerizable resin and fluorescing compound, is applied to a tooth surface and cured so that it hardens. The composition is preferably used as a dental sealant that provides a hard, glossy surface finish over a tooth. Upon irradiating the sealant with ultraviolet light, the sealant exhibits a bright fluorescent glow. The sealant reverts immediately to its natural color when it is no longer exposed to the ultraviolet light.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 11/541,065 filed onSep. 29, 2006, which claims the benefit of U.S. Provisional ApplicationSer. No. 60/721,706 having a filing date of Sep. 29, 2005, the entirecontents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to methods for using dentalcompositions containing polymerizable resins and fluorescent compounds.The dental compositions can be used as flowable composites (fillings),adhesives, sealants, and the like. The dental compositions arepreferably used as dental sealants.

2. Brief Description of the Related Art

Dental professionals apply a sealant to the surface of a tooth in orderto provide long-term protection against dental caries, which is causedby the accumulation of bacteria. The bacteria in plaque produce acidsthat eat into the tooth, eventually causing cavities to form therein.Pits and fissures may develop in the surface of a tooth, and bacteriatend to accumulate in these areas. Sealants are commonly used to fillthe pits and fissures in the surface of a tooth, particularly theocclusal surfaces of posterior teeth. The sealants, once applied andcured, provide a smooth seal and prevent the ingress of fluids, food,and debris. The sealant can either have a clear composition or opaquecomposition to match the color of the tooth. Both types of sealantcompositions tend to have a glossy surface finish and provide anaesthetically-pleasing appearance.

The dental professional must apply the sealant carefully so that itcompletely seals the pits and fissures in the surface of the tooth.Typically, the sealant is applied with a brush or other applicator.Then, the sealant is cured and hardened. The curing step normallyinvolves irradiating the sealant with blue visible light having awavelength generally in the range of about 400 to about 700 nm. Theapplication and curing of the sealant can be difficult. When a clearsealant composition is used, the dentist may have trouble discerningbetween the pits and fissures, which need to be sealed, versus healthydentition. It also can be difficult to apply an opaque sealantcomposition, because the color of the sealant composition and naturalcolor of the tooth can be substantially the same. Another problem withsome conventional sealants is that they tend to wear-away over time.When the dentist examines the patient in follow-up visits, he or she maynot be able to easily detect if portions of the sealant have worn off.As part of an effort to address these problems, the dental industry hasdeveloped dental sealants containing fluorescing compounds. With thesefluorescing sealants, the dental professional is better able to checkmargins and determine if the sealant has been placed accurately on thesurface of the tooth during initial patient visits. In follow-up visits,the dentist can examine the patient's tooth, under fluorescingconditions, to determine if the sealant has worn off.

For example, Schwartz, U.S. Pat. No. 4,600,389 discloses dentalcompositions used for making restorations, inlays, onlays, crowns,sealants, glazes, and cements. The composition contains microbeadshaving a fluorescent rare earth chelated compound therein. Thefluorescent rare earth compound is permanently isolated within themicrobeads. The composition is colorless when viewed under ordinarydaylight, sunlight, or disco light but is highly fluorescent whenexposed to ultraviolet radiation having a wavelength of 300 to 400 nmaccording to the '389 patent.

Rheinberger et al., U.S. Pat. No. 5,102,461 relates to a colorlessdental material that can be distinguished from natural teeth, falseteeth, and other dental materials. The colorless dental materialincludes a fluorescent substance that emits fluorescent light as aresult of being irradiated with radiation having a wavelength in theregion of 360 to 480 nm. Suitable dental materials, which can be made inaccordance with the '461 patent, include spacer varnishes, blockingmaterials, composite filling materials, cements, and sealants. Thedental material is irradiated with light having a wavelength in theregion of 360 to 480 nm, and the material is viewed through a lightfilter. The '461 patent teaches that the interfering effects caused byreflection of the irradiating light (360 to 480 nm) and the naturalfluorescence of teeth are overcome by using the light filter.

Robinson et al., U.S. Pat. No. 5,211,748 discloses a dental restorativecomposition containing an additive that fluoresces under radiationhaving a wavelength in the visible light spectrum. The preferredadditive is chromium-activated “crushed ruby.” According to the '748patent, a conventional light source, such as a blue light used forcuring dental composites, can be used to irradiate the composition withthe required visible light. The ruby additive fluoresces when irradiatedby visible-wavelength light but does not fluoresce when irradiated byultra-violet light.

Although some of the foregoing dental compositions can be usedeffectively as dental sealants, there is still a need for an improvedcomposition. It would be particularly desirable to use a fluorescentcompound, which does not impart any substantial color to thecomposition. The sealant, containing the fluorescent compound, wouldmaintain its ordinary color after it had been applied to the surface ofthe tooth and while it was in an uncured condition. The sealant wouldmaintain this same color after it had been cured. It also would bedesirable to have a composition, which would fluoresce upon beingirradiated with ultraviolet light, but would revert quickly to itsordinary color when it was no longer exposed to the ultraviolet light.The present invention provides a dental sealant having these desirableproperties as well as other features and advantages.

SUMMARY OF THE INVENTION

The present invention provides a method of applying a dental compositionto tooth surfaces. A dental composition comprising polymerizable resinand fluorescing compound is provided. The composition is applied to atooth surface and cured so that it substantially hardens. Then, thecomposition is irradiated with a light source emitting light at awavelength in the ultraviolet spectrum of about 200 to about 400 nm. Thecomposition is visually identified by observing the composition emittingfluorescence having a wavelength in the visible spectrum of greater thanabout 400 nm. This allows the dental practitioner to distinguish thearea of the tooth containing the composition from remaining naturalareas of the tooth surface.

The fluorescent compound is preferably 7-diethylamino-4-methylcoumarin.The composition is preferably used as a dental sealant that provides ahard, glossy surface finish over a tooth. The sealant exhibits a brightfluorescent glow immediately upon being exposed to ultraviolet light.The sealant reverts immediately to its natural color when it is nolonger exposed to the ultraviolet light. Only a low dosage ofultraviolet light is needed to excite the fluorescent compound in thecomposition.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to methods of using a dental compositioncontaining a polymerizable resin and fluorescent compound. Preferably,the dental composition is used as a sealant on tooth surfaces.

The dental composition of this invention contains a polymerizable resinsuch as, for example, acrylate resins, methacrylate resins, or mixturesthereof. Such acrylate and methacrylate resins are well known in the artand include, for example, polymerizable monomers and oligomers such asethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate,Methylene glycol di(meth)acrylate, tetraethylene glycoldi(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butanedioldi(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropanetri(meth)acrylate, 2,2-bis[4-(2-hydroxy-3-acryloyloxypropoxy)phenyl]propane, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (Bis-GMA), 2,2-bis[4-(acryloyloxy-ethoxy)phenyl]propane,2,2-bis[4-(methacryloyloxy-ethoxy)phenyl]propane, urethanedi(meth)acrylate (UDMA), and the like.

In addition to the foregoing monomers and oligomers, the composition maycontain diluent monomers such as hydroxy alkyl methacrylates; ethyleneglycol methacrylates; and diol methacrylates such as tri(ethyleneglycol) dimethacrylate (TEGDMA) to reduce viscosity and make thecomposition more suitable for application. The monomers and oligomersare typically present in the composition in an amount in the range ofabout 10% to about 99% based on the total weight of the composition andpreferably in an amount in the range of about 20% to about 60%.

The composition can be self (chemically)-curable and/or light-curable.The composition may contain a photoactive agent such as, for example,benzophenone, benzoin and their derivatives or alpha-diketones and theirderivatives in order to make the composition light-curable. Aparticularly preferred photoinitiator is camphorquinone (CQ).Preferably, photopolymerization is initiated by irradiating thecomposition with blue, visible light preferably having a wavelength inthe range of about 400 to about 500 nm. A standard dental bluelight-curing unit can be used to irradiate the composition.

The camphorquinone (CQ) compounds have a light absorbency maximum ofbetween about 400 to about 500 nm and generate free radicals forpolymerization when irradiated with light having a wavelength in thisrange. Alternatively, the photoinitiator can be selected from the classof acylphosphine oxides such as, for example,2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide. The photopolymerizationinitiators are typically present in the composition in the range ofabout 0.1 to about 10 wt. % and preferably in the range of about 0.1 toabout 2 wt. %.

Furthermore, the composition may be self-curable and contain apolymerization initiator such as peroxide. For example, dibenzoylperoxide, di-p-chlorobenzoyl peroxide, di-2,4-dichlorobenzoyl peroxide,tertiary butyl peroxybenzoate, methyl ethyl ketone peroxide, ditertiarybutyl peroxide, dicumyl peroxide, cumene hydroperoxide, and the like canbe added to the composition. Polymerization accelerators, particularlytertiary amines also may be added to the composition to increase therate of polymerization. In instances, where the composition will becured by visible light, the tertiary amines are generally acrylatederivatives such as dimethylaminoethyl methacrylate, diethylaminoethylmethacrylate, and the like. In the self-curing compositions, thetertiary amines are generally aromatic tertiary amines such as, forexample, N-methyl-diethanolamine, ethyl 4-(dimethylamino)benzoate(EDMAB), 2-[4-(dimethylamino)phenyl]ethanol, N, N-dimethyl-p-toluidine(DMPT), dihydroxyethyl-p-toluidine (DHEPT),bis(hydroxyethyl)-p-toluidine, triethanolamine, and the like.

In one form of the invention, the composition is provided as apaste-like material in a single package. In such instances, thecomposition typically is light-curable and contains a photoinitiator andpolymerization accelerator as discussed above. Conventional dispensingsyringes, applicators, brushes, and other delivery devices can be usedto apply the composition to the desired area of the tooth orpre-existing dental restoration. In one embodiment, the composition isprovided in a single cartridge, which is inserted into a barrel of adispensing syringe. In practice, a dentist pushes on the plunger of thesyringe to force the composition from the cartridge and through adispensing tip. The composition is dispensed onto the targeted area ofthe tooth or dental restoration in this manner. Then, the compositioncan be cured or hardened by irradiating the composition with visiblelight radiation. A standard, visible blue light dental-curing unit canbe used to cure the composition in this manner.

In another form of the invention, the composition is provided as atwo-part, auto-curable system. A catalyst paste is provided in onepackage, and a base paste is provided in a second package. The catalystpaste may include a polymerizable monomer such as ethoxylatedbisphenol-A-dimethacrylate and a catalyst such as dibenzoyl peroxide.The base paste may include a polymerizable monomer, which is differentthan the polymerizable monomer used in the catalyst paste, and apolymerization accelerator such as a tertiary amine. The fluorescentcompound used in the composition of this invention, as discussed infurther detail, below, can be added to either the catalyst or basepastes or both pastes. An auto-mix delivery system such as, for example,a double barrel syringe, can be used to mix the catalyst and basecomponents and dispense the resulting composition. The catalyst and basepastes are stored in separate cartridges and dispensed from thecartridges in a pre-determined volume ratio and mixed together to formthe composition. The resulting, mixed composition is delivered throughthe dispensing tip of the syringe and onto the targeted area. As thecatalyst and base pastes are mixed together, the amine and peroxidereact with each other and initiate polymerization and curing of thecomposition. Thus, the dentist has only a short working time when usingthis two-part system. The catalyst and base pastes are not mixedtogether until just before the dentist is ready to apply thecomposition.

In other instances, the catalyst and base pastes can be stored inseparate applicator tubes. The catalyst and base pastes are dispensedfrom their respective applicator tubes and into a mixing dish. Then, thecatalysts and base pastes can be mixed together by hand to form thefinal composition that will be applied to the tooth or dentalrestoration.

The dental composition may further contain conventional organic orinorganic fillers. Alternatively, the composition may be unfilled.Examples of conventional fillers include glass, quartz, bariumborosilicate, strontium borosilicate, borosilicate, barium silicate,strontium silicate, lithium silicate, lithium alumina silicate, calciumphosphate, alumina, zirconia, tin oxide, titanium dioxide, and the like.Such fillers typically have a particle size in the range from about 0.1to about 5.0 microns and are silane-treated in order to improve thebonding between the fillers and resin matrix. The composition istypically partially filled, and the amount of filler particles in thecomposition is typically in the range of about 10% to about 70% based onthe total weight of the composition and preferably in the range of about20% to about 60%. In other embodiments, the dental composition isunfilled, and there are no filler particles present in the composition.

The dental composition of this invention contains a fluorescent compoundthat is highly emissive and will impart a fluorescent glow to thecomposition when irradiated by an ultraviolet light source. Thefluorescent compound is preferably 7-diethylamino-4-methylcoumarin.Several factors need to be considered when adding the fluorescentcompound to the sealant composition. As in the case of many addedcomponents, the fluorescent compound can have both a positive andnegative impact on the properties of the final composition. Thispotential trade-off in properties makes it difficult to add suchcomponents.

For example, adding a relatively low amount of fluorescent compound iseconomically advantageous, but it will not provide the sealantcomposition with sufficient fluorescence. On the other hand, adding arelatively high amount will impart a glowing fluorescence to thecomposition, but such high amounts also can cause deleterious changes tothe physical properties of the composition. Particularly, the mechanicalstrength and wear-resistance can be reduced if a very high amount offluorescent compound is added. Additionally, the fluorescent compoundmay impart some undesirable color to the composition.

Of the many possible fluorescent compounds that could be added to thecomposition, it was found that 7-diethylamino-4-methylcoumarin providesthe most desirable properties. The 7-diethylamino-4-methylcoumarin isadded in an amount effective to impart sufficient fluorescence to thecomposition. The amount of 7-diethylamino-4-methylcoumarin in thecomposition is not particularly restricted, and generally will be in therange of about 0.01 to about 15.00 weight percent (wt. %). But, it wasfound unexpectedly that only about 0.20 percent by weight (wt. %) of7-diethylamino-4-methylcoumarin is needed to provide sufficientfluorescence. Moreover, it was found that adding 0.20 wt. % of7-diethylamino-4-methylcoumarin does not negatively impact the physicalproperties or change the color of the composition.

Energy in the ultraviolet light spectrum is used to excite thefluorescent compound. Once excited, the fluorescent compound will emitenergy in the visible light spectrum at a level sufficient to provide abright, fluorescent glow. As a result, the dentist can easily identifythe areas on the surface of the tooth, where the sealant composition hasbeen applied. The dentist can make a visual distinction between pits andfissures, which have been filled with the fluorescent sealant, overnatural areas of dentition. The fluorescent glow of the sealant allowsthe dentist to better check margins and accurately apply the sealant toonly those areas of the tooth, where treatment is needed. Duringfollow-up visits with the patient, the dentist can irradiate the toothwith ultraviolet radiation. Under these fluorescing conditions, thesealant, if present on the tooth, will exhibit a bright, fluorescentglow. This feature allows the dentist to determine if the sealant hasworn away from any areas of the tooth.

As discussed above, the compositions of this invention are preferablyused as dental sealants. It is contemplated that the above-describedfluorescent compounds could be added to commercially-available dentalsealant compositions such as, for example, DELTON; DELTON PLUS; andDYRACT (Dentsply International); BISCOVER (Bisco, Inc.); SEAL-N-SHINE(Pulpdent Corp.); and OPTIGARD (Kerr Manufacturing). Other commercialdental sealant compositions can be used in accordance with thisinvention.

In addition to the fluorescent compounds, the composition can containadditives such as flavoring agents, anti-microbial agents, plasticizers,anti-oxidants, viscosity modifiers, and the like. Preferably, afluoride-releasing agent or filler is added to the composition. Forexample, a fluoride-releasing glass such as fluoro-alumino-silicate maybe added to the composition. The fluoride-releasing glasses provide thebenefit of long-term release of fluoride. Fluoride salts such as, forexample, sodium fluoride also can be used in the composition. Onebenefit with adding a fluoride source to the composition is that thefluoride provides added protection against acid attack that causes toothdecay. The composition may contain a mixture of fluoride-releasingglasses and fluoride salts to provide a staged period of fluoriderelease. For example, the sodium fluoride or other fluoride salt can beadded to provide a quick burst of fluoride. To complement the fluoridesalt, a fluoridated glass, which provides a longer, slower rate offluoride release, can be added.

The compositions of this invention can be used as various dentalmaterials including, for example, as flowable composites (fillings),adhesives, sealants, and the like. Preferably, the composition is usedas a dental sealant for sealing pits and fissures in the surface of atooth. The sealant can have either a clear or opaque composition. Thesealant is applied to the surface of the tooth so that it provides asmooth and glossy surface finish. The sealant coating is hard andnon-tacky. In addition, the sealant coating has good mechanicalstrength, wear-resistance, and adhesion strength. The sealant may beapplied to the surface of a tooth using methods well known in the art.First, the surface of the tooth is cleaned thoroughly. Prophylaxispastes can be used to clean the surface of the tooth. Secondly, thesurface of the tooth is dried with cotton rolls, an air syringe, orother appropriate materials. Thirdly, the surface of the tooth isacid-etched. Liquid etchant can be brushed onto the surface of the toothto prepare an etched surface. Then, the surface of the tooth is driedagain. Fourthly, the sealant is applied to the etched surface of thetooth with a brush or other suitable applicator. The uncured dentalsealant has a syrup-like consistency. The dental sealant of thisinvention preferably has an off-white color. But, it should berecognized that the sealant might be formulated so that it has anysuitable color. Colorants may be added to the sealant composition tomodify the color as desired. The fluorescing compound imparts nosubstantial color to the sealant. Finally, the sealant is cured byirradiating it with visible blue light having a wavelength in the rangeof about 400 to about 800 nm. A standard blue light dental-curing lampcan be used to cure the sealant. The color of the sealant remainssubstantially the same even when the sealant has been cured with visiblelight. For example, if the sealant has a natural off-white color when itis in an uncured state, its color will remain off-white after the curingstep has been completed.

When the dentist wishes to check the placement of the sealant, he or sheirradiates the sealant with ultraviolet light having a wavelength in therange of about 200 nm to about 400 nm. Preferably, ultraviolet lighthaving a wavelength in the range of about 365 nm to about 390 nm isused. As discussed above, energy in the ultraviolet light spectrum isused to excite the fluorescent compounds. In turn, the fluorescentcompounds, will emit energy in the visible light spectrum at a levelsufficient to provide a fluorescent glow, particularly a bluish-whitefluorescent glow. The response to the ultraviolet light is immediate. Anunaided human eye instantaneously sees the fluorescent glow of thesealant composition once the composition is exposed to ultravioletlight. The fluorescent glow of the composition is bright and clear, anda human observer can immediately discern materials that contain thecomposition over non-fluorescing materials. Moreover, the dentist caninspect a tooth and easily distinguish between the areas of the tooth,which have been treated with the sealant of this invention, versus thoseareas, which have not been treated with the sealant. The dentist removesthe ultraviolet light source after completing his or her examination ofthe patient. Immediately at this point, when the tooth is no longerexposed to the ultraviolet light, the sealant reverts to its ordinarycolor (for example, off-white). The response to removing the ultravioletlight source is instantaneous. An unaided human eye will instantaneouslyobserve the natural color of the sealant composition once theultraviolet light source has been removed.

Any light source, which emits ultraviolet light, such as, for example,lamps, flashlights, lasers, light-emitting diodes, and the like can beused to illuminate the sealant composition of this invention. Forexample, a light-emitting, stylus-like device can be used as theultraviolet light source. The stylus-like device is preferablylightweight and battery-operated. The stylus-like device containslight-emitting diodes that emit ultraviolet radiation. Generally, suchstylus-like devices are easier to handle and operate than standardvisible-light dental curing lamps. Furthermore, since the compositionsof this invention respond immediately upon being exposed to theultraviolet light, only a low dosage of ultraviolet radiation is needed.A dentist can grasp the stylus-like device and focus the ultravioletlight directly on the tooth or dental restoration. The dentist willimmediately observe a fluorescent glow emanating from the tooth orrestoration if the composition is present thereon.

The dental compositions of the present invention have many advantageousproperties and benefits including the following. First, the compositionexhibits a fluorescent glow immediately upon being exposed to theultraviolet light. Conversely, when the composition is no longer exposedto the ultraviolet light, it reverts immediately to its natural color.In other words, the composition has an instantaneous on/off fluorescencemechanism. Secondly, the fluorescing compound imparts no substantialcolor to the sealant. Adding the fluorescent compound to the sealantcomposition does not change the natural color of the composition.Thirdly, a light-emitting, stylus-like device can be used as theultraviolet light source. The device is preferably lightweight andbattery-operated. Only a low dosage of ultraviolet energy is needed toexcite the fluorescent compounds so that the composition gives off afluorescent glow. Fourthly, the amount of fluorescent compound, whichneeds to be added to the composition to impart sufficient fluorescence,is relatively low. In general, only about 0.2 percent by weight (wt. %)of fluorescent compound is needed in accordance with this invention.

The invention is further illustrated by the following Examples, butthese Examples should not be construed as limiting the scope of theinvention.

EXAMPLES Example 1

A dental sealant composition as described in below Table 1 was prepared.

TABLE 1 Component Weight Percentage (Wt. %) Mixture of Bis-GMA, urethanemodified 58.50% Bis-GMA dimethacrylate, and dimethacrylate resinSilanated barium-fluoro-alumino 38.00% borosilicate glass Titaniumdioxide 0.70% Sodium fluoride 2.00% Silicon dioxide 0.60%7-diethylamino-4-methylcoumarin 0.20%

The ingredients were introduced into a planetary mixer at ambienttemperature and mixed together. After the ingredients were mixed for onehour, they were processed through a colloid mill to break-up anyagglomerates. Lastly, the composition was mixed under vacuum to removeany entrained air.

The resulting sealant composition was applied as a sealant to a set ofmounted, extracted teeth that were used as test specimens. Thecomposition was tested for fluorescence in its uncured and cured states.An ultraviolet light source was used to illuminate the sealant-coatedteeth. The composition immediately exhibited a fluorescence glow uponbeing exposed to the ultraviolet light. The fluorescent regions of thetooth, where the sealant composition had been applied, were easilyidentifiable and distinguishable over natural dentition of the tooth.Once the ultraviolet light source was removed and the tooth no longerilluminated, the sealant composition immediately reverted to its naturaloff-white color. In addition, the sealant composition was tested forvarious physical properties and the results are reported below in Table3.

Comparative Example A

For comparison purposes, a sealant composition, which did not contain afluorescent compound, was prepared and tested.

The formulation described in below Table 2 was used to prepare thecomparative sealant composition. The comparative sealant composition wasprepared in the same manner used to prepare the composition in Example1.

TABLE 2 Component Weight Percentage (Wt. %) Mixture of Bis-GMA, urethanemodified 58.70% Bis-GMA dimethacrylate, and dimethacrylate resinSilanated barium-fluoro-alumino 38.00% borosilicate glass Titaniumdioxide 0.70% Sodium fluoride 2.00% Silicon dioxide 0.60%

The above-comparative sealant composition was applied as a sealant to aset of mounted, extracted teeth that were used as test specimens. Thecomposition was tested for fluorescence in its uncured and cured states.An ultraviolet light source was used to illuminate the sealant-coatedteeth. The composition did not exhibit any fluorescence glow. Inaddition, the comparative sealant composition was tested for variousphysical properties and the results are reported below in Table 3.

TABLE 3 Property Example A (no dye) Example 1 (dye added) DiametralTensile (PSI) 7158 7100 Water Sorption at 0.9 0.7 37° C. (mg/cm) UncuredFilm Thickness, % 0.7 0.6 Depth of Cure (mm) 4 4 Compressive Strength(PSI) 44,570 +/− 3113   44,563 +/− 8734   Abrasion (% Weight Loss) 5.40+/− 0.72 5.09 +/− 0.86 Shear Bond Strength to 19.4 +/− 2.9  20.2 +/−4.0  Enamel (1800 Thermocycles, MPa)

As shown in Table 3, there is no significant difference in the physicalproperties of the sealant composition of Example 1 that contains thefluorescent compound, 7-diethylamino-4-methylcoumarin; and the sealantcomposition of Comparative Example A that does not contain thefluorescent compound. Example 1 and Comparative Example A demonstratethat the fluorescent compound used in the sealant compositions of thisinvention does not interfere with the mechanical strength or otherphysical properties of the compositions.

Workers skilled in the art will appreciate that various modificationscan be made to the illustrated embodiments and description hereinwithout departing from the spirit and scope of the present invention. Itis intended that all such modifications within the spirit and scope ofthe invention be covered by the appended claims.

1. A method of applying a dental composition to an area of a toothsurface, comprising the steps of: a) providing a dental compositioncomprising polymerizable resin and fluorescing compound, wherein thefluorescing compound includes 7-diethylamino-4-methylcoumarin; b)applying the composition to a tooth surface; c) curing the compositionso that it hardens; d) irradiating the composition with a light sourceemitting light at a wavelength in the ultraviolet spectrum of about 200to about 400 nm; and e) visually identifying the composition byobserving emitted fluorescence having a wavelength in the visiblespectrum of greater than about 400 nm so as to distinguish the area ofthe tooth surface containing the composition from remaining naturalareas of the tooth surface.
 2. The method of claim 1, wherein thepolymerizable resin is selected from the group consisting of acrylateand methacrylate resins and mixtures thereof.
 3. The method of claim 1,wherein the composition is light-curable and comprises a photoinitiator.4. The method of claim 3, wherein the photoinitiator is camphorquinone.5. The method of claim 1, wherein the composition is self-curable andcomprises a polymerization initiator.
 6. The method of claim 5, whereinthe polymerization initiator is peroxide.
 7. The method of claim 1,wherein the composition further comprises a filler material selectedfrom the group consisting of organic and inorganic fillers.
 8. Themethod of claim 7, wherein the filler material is fluoro-aluminoborosilicate glass.
 9. The method of claim 1, wherein the compositionfurther comprises sodium fluoride.
 10. The method of claim 1, whereinthe 7-diethylamino-4-methylcoumarin is about 0.2 percent by weight ofthe dental composition.
 11. The method of claim 1, wherein thefluorescing compound is in the range about 0.2 percent by weight toabout 15 percent by weight of the dental composition.
 12. The method ofclaim 1, wherein the fluorescing compound is present in an amountsufficient to provide fluorescence when exposed to the light sourceemitting light in the ultraviolet spectrum of about 200 to about 400 nmwithout changing the color of the dental composition when the lightsource is not emitting light in the ultraviolet spectrum of about 200 toabout 400 nm.
 13. A method of applying a dental composition to an areaof a tooth surface, comprising the steps of: a) providing a dentalcomposition comprising polymerizable resin and fluorescing compound,wherein the fluorescing compound does not impart color to the dentalcomposition and wherein the fluorescing compound is7-diethylamino-4-methylcoumarin and is present as about 0.2 percent byweight of the dental composition; b) applying the composition to a toothsurface; c) curing the composition so that it hardens; and d)irradiating the composition with a light source emitting light at awavelength in the ultraviolet spectrum of about 200 to about 400 nm tocause emitted fluorescence having a wavelength in the visible spectrumof greater than about 400 nm.